In conventional paper making processes, the paper is formed upon high speed endless belts which absorb the moisture to the extent where the sheet of partially formed paper can be separated from the belt and further processed. The felt belts are then normally passed over conditioning boxes which extract the moisture and any contaminants which may be on the belts, thus preparing the belts for further use immediately.
Felt conditioning boxes usually include an enclosure extending the full width of the belt, said enclosure being provided with a narrow transverse slot and a source of reduced air pressure or vacuum is connected to the box thus drawing air downwardly through the belt passing over the slot and removing the moisture at the same time.
The belt is supported and guided across the slot by stainless steel rods, but due to the high speed of the belt and the relative abrasive quality of the material used in the manufacture of the belts, the steel rods rapidly become worn and the sharp edges formed by this wear, initiates severe damage to the belts which are, of course, relatively expensive.